1. Field of the Invention
The present invention relates to a device serving to take from a pile a knitted or woven article, to displace the article thus taken and to place it at a pre-arranged place.
2. Description of the Prior Art
Devices of this type are already known, particularly by virtue of French Pat. Nos. 2 011 087 and 2 132 573, which describe a device including one or more gripping means each constituted by a retractible, oblique needle that can be displaced along a rectilinear path. When each needle is pushed so as to project, it penetrates the thickness of the article to be selected by an amount sufficient to lift this article when the device as a whole is itself raised.
Although it is possible to use on one and the same device several needle type gripping means disposed in diverging or even opposed directions, for example from the centre to the outside of the article to be displaced, satisfactory results are not obtained when the knitted articles reach any considerable size. In this case, the weight of the article causes it to droop considerably between the gripping points and it may even become detached during lifting. Even if the weight is not sufficient to cause it to become detached, the drooping portions hinder displacement and are prejudicial to precise positioning of the article transported.
In order to remedy the above drawbacks, it has been proposed to use the combined action of a needle type gripping means and of a vacuum type gripping means. Different forms of embodiment of a combination of this type are disclosed in the following patents: French Pat. Nos. 85 309 (certificate of addition)-2 011 072 (certificate of addition)-2 104 132-2 109 407 (certificate of addition) 2 041 874- and U.S. Pat. No. 3,386,396.